home   contributing   bugs   download   online pages  

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | NOTES | SEE ALSO | COLOPHONThe Linux Programming Interface


MBTOWC(3)                     Linux Programmer's Manual                     MBTOWC(3)

NAME         top

       mbtowc - convert a multibyte sequence to a wide character

SYNOPSIS         top

       #include <stdlib.h>

       int mbtowc(wchar_t *pwc, const char *s, size_t n);

DESCRIPTION         top

       The main case for this function is when s is not NULL and pwc is not NULL.  In
       this case, the mbtowc() function inspects at most n bytes of the multibyte
       string starting at s, extracts the next complete multibyte character, converts
       it to a wide character and stores it at *pwc.  It updates an internal shift
       state only known to the mbtowc function.  If s does not point to a '\0' byte,
       it returns the number of bytes that were consumed from s, otherwise it returns
       0.

       If the n bytes starting at s do not contain a complete multibyte character, or
       if they contain an invalid multibyte sequence, mbtowc() returns -1.  This can
       happen even if n >= MB_CUR_MAX, if the multibyte string contains redundant
       shift sequences.

       A different case is when s is not NULL but pwc is NULL.  In this case the
       mbtowc() function behaves as above, except that it does not store the
       converted wide character in memory.

       A third case is when s is NULL.  In this case, pwc and n are ignored.  The
       mbtowc() function resets the shift state, only known to this function, to the
       initial state, and returns nonzero if the encoding has nontrivial shift state,
       or zero if the encoding is stateless.

RETURN VALUE         top

       If s is not NULL, the mbtowc() function returns the number of consumed bytes
       starting at s, or 0 if s points to a null byte, or -1 upon failure.

       If s is NULL, the mbtowc() function returns nonzero if the encoding has
       nontrivial shift state, or zero if the encoding is stateless.

CONFORMING TO         top

       C99.

NOTES         top

       The behavior of mbtowc() depends on the LC_CTYPE category of the current
       locale.

       This function is not multithread safe.  The function mbrtowc(3) provides a
       better interface to the same functionality.

SEE ALSO         top

       MB_CUR_MAX(3), mbrtowc(3), mbstowcs(3)

COLOPHON         top

       This page is part of release 3.32 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can be found
       at http://www.kernel.org/doc/man-pages/.

GNU                                   2001-07-04                            MBTOWC(3)

HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface

customisable
counter